The WP Database Backup plugin for WordPress is vulnerable to OS Command Injection in versions before 5.2 via the mysqldump function. This vulnerability allows unauthenticated attackers to execute arbitrary commands on the host operating system.
The WP Database Backup WordPress plugin before 5.9 does not escape some of its settings, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting attacks when the unfiltered_html capability is disallowed (for example in multisite setup)
The WP Database Backup plugin through 5.5 for WordPress stores downloads by default locally in the directory wp-content/uploads/db-backup/. This might allow attackers to read ZIP archives by guessing random ID numbers, guessing date strings with a 2020_{0..1}{0..2}_{0..3}{0..9} format, guessing UNIX timestamps, and making HTTPS requests with the complete guessed URL.